When asked on "Good Morning America" Thursday if it was a hard decision to miss joining her band members -- Melanie Brown, Emma Bunton, Geri Halliwell and Melanie Chisholm – for their first tour in over a decade, Beckham replied simply, "You know, it wasn't."

"I’ll always be a Spice Girl and I’m so proud of everything I achieved. I’m so proud of them," she said. "It’s going to be the best show."

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British all-girl singing group the Spice Girls at the Brit Awards, where they won in the Best Video and Best Single categories, Feb. 24, 1997.

Beckham, a mother of four, added, "I can’t wait to take the kids and see it but, you know, with my business now I just wouldn’t be able to do it, but I wish them so much luck."

"I have been working in high fashion now for 10 years but working on a sports line is something very new," she said. "I want to learn and I have learned an enormous amount."

Beckham, who called her husband of 20 years, soccer legend David Beckham, her "soulmate," is known for being a devoted exerciser. She said the collaboration with Reebok emerged from a need she had as a busy mom and the head of a global fashion company.

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David Beckham and Victoria Beckham attend the Fashion Awards 2018 at Royal Albert Hall, Dec. 10, 2018, in London.

"I always want to create what I want in my life," Beckham said. "As a woman, what do I need?"

"I work out a lot. It’s a huge part of me, of what I do every day. I get up. I work out. I take the kids to school," she said. "So I wanted clothes that, yes, did what I wanted them to do in the gym, but then also clothes that would take you through the day."

Beckham designed the collection to be unisex, so men can wear it, too. The collection, available now, includes everything from a $500 bomber jacket to a $90 tank top, $280 shoes, running socks, backpacks and more.

"Never did I think it would be acceptable to leave the house in a track suit, and now it is," Beckham said as a model showed one of the looks, sweatpants paired with a sweatshirt. "It looks cool. It still feels fashion. It’s effortless."